P and D both sell non-prescription eyeglasses. P is the assignee of Patents '532, '345, '726, and '911. The patents claim technology for displaying eyeglasses on racks. The claimed inventions allow consumers to try on eyeglasses and return them to the rack without removing them from their display hangers. P sued D for infringement. The district court construed the 'eyeglass hanger member' element of the '345 patent as a means-plus-function claim element subject to § 112, P 6. The court instructed the jury that 'the 'eyeglass hanger member for mounting a pair of eyeglasses' is the body of the hanger disclosed in the '345 patent and its drawings and the structural equivalents thereof. The court interpreted the 'eyeglass hanger member' element of the '726 patent in the same way. The district court instructed the jury that 'the 'eyeglass hanger member for mounting a pair of eyeglasses' is the hanger disclosed in the '726 patent and its drawings as having a body, an aperture, and an attaching portion and the structural equivalents thereof. On the '911 patent, the court concluded that the 'eyeglass contacting member' was a means-plus-function element. It instructed the jury that the eyeglass contacting member' is 'the hanger disclosed in the '911 patent and its drawings having a body and an aperture and an 'encircling portion' and the structural equivalents thereof. The jury determined that one of D's products (the Version 1 hanger tag) literally infringed the '532 patent. The jury determined that a second VSI product (the Version 2 hanger tag) did not literally infringe the '345, '726, and '911 patents, but did infringe those patents under the doctrine of equivalents. The jury concluded that the P patents were not invalid under 35 U.S.C. § 103. P moved for judgment as a matter of law that the Version 2 hanger tag literally infringed the '345, '726, and '911 patents. The district court denied the motion and both P and D appealed. P challenges the district court's claim construction of the '345, '726, and '911 patents, arguing that the claims, if properly construed, would have been literally infringed by VSI's Version 2 hanger tag.